Ling did from LingsCars (appeared on Dragons Den) she put a rocket on an old military vehicle and parked it near a motorway, very effective but I don't think the council were too chuffed.
I met her a wee while back; didn't know it was her 'till I got talking to her. The mad 'bag lady' image she displayed on Dragon's Den is just a facade and she's actually quite a refined, very intelligent young woman.
There are a few instances of similar sorts of things along the M8... Farmer's fields with trailers parked in them; Ads on the side.... Where you have a bit of space and the 'board can become a landmark there's a possible benefit. In fact isn't there at least one 'real' billboard on the M8? More conventional billboards are HORRENDOUSLY expensive to use... Good for products that require a strong 'sub conscious' presence. But they're more a useful component part of a broad ad campaign than anything you'd benefit from directly.
When I ran Clydeside TV as a corporate production company (the name's now only used for broadcast and sell-through) We used to take space on the backs of buses and sides of taxis. This was as a support to another (radio) campaign... An ad on the back of a bus (which is getting showed under people's nose upteen times per day) was about 1/10th of the cost of a single billposter site.... Bus shelters and street furniture site are more useable. But didn't we have a post of the old board about some city council wanting